Can a reduced hospital stay for young infants with possible serious bacterial infection (PSBI) lead to similar or improved treatment outcomes compared to existing WHO guidelines?

INTERVENTION: Young infants (YIs) <2 months old visiting outpatient clinics or emergency rooms of participating hospitals will be screened for one low‐mortality risk sign of CSI (study‐1) or one high‐mortality risk sign/multiple low‐mortality risk sign of CSI (Study‐2). For study‐1, YIs will be consented and randomised through a sealed envelope for outpatient/home treatment (intervention group) or inpatient/hospital treatment (control group). The outpatient treatment with injectable gentamicin (once daily) for 2 days plus oral amoxicillin (twice daily) for 7 days. The inpatient antibiotic treatment for at least 7 days initiated with WHO recommended antibiotic regimen of injectable ampicillin (four time daily) plus injectable gentamicin (once daily) along with other supportive care. Outcome assessment will be carried by visiting all enrolled young infants on day 2, 4, 8 and 15 after enrolment. Outcome assessment will be conducted at the hospital or at home after discharge in the control arm and at home in the intervention arms. Outcomes will only be ascertained by the IOAs in accordance with the outcomes criteria For study‐2, YIs who were admitted at the study hospital with relatively higher‐mortality risk signs of CSI at presentation/screening will be assessed for eligibility for this study 48 h after initiation of treatment and considered for inclusion in the study if: i) clinically well on day 3 defined as absence of all signs of critical illness or CSI, and ii) Laboratory test (CRP) negative. They will be randomised using sealed envelope and assigned to intervention or control treatment group. In the intervention group, they will be discharged from hospital and treated at home with oral antibiotics for 5 days. The control group wi CONDITION: Critical severe infection (CSI) or critical illness of Possible Serious Bacterial Infection (PSBI) in sick young infants ; Infections and Infestations PRIMARY OUTCOME: ; Measured using case report forms completed at follow up:; ; Study‐1:; 1. Death any time from randomization up to day 15 of initiation of therapy; 2. Presence of any sign of critical illness (no movement at all, unable to feed at all, or convulsions) or any sign suggestive of another serious infection, e.g. meningitis, bone or joint infection, on day 2, 4 or day 8 of initiation of therapy; 3. Presence of any new sign of CSI on day 4 or day 8 of initiation of therapy; 4. Persistence of the presenting sign on day 8 of the initiation of therapy; ; Study‐2:; 1. Death between randomization (day 3 of initiation of therapy) and day 15 of initiation of therapy; 2. Presence of any sign of critical illness (no movement at all, unable to feed at all, or convulsions) or any sign suggestive of another serious infection, e.g. meningitis, bone or joint infection, on day 8 of initiation of therapy; 3. Presence of any sign of CSI on day 8 of initiation of therapy; SECONDARY OUTCOME: There are no secondary outcome measures INCLUSION CRITERIA: Study‐1: 1. Aged <2 months 2. Living in a geographic area where follow‐up for 14 days can be accomplished presenting to outpatient clinics or emergency rooms of participating hospitals 3. ONLY one of the following low‐risk signs of PSBI: 3.1. Body temperature =38°C 3.2. Severe chest indrawing 3.3. Fast breathing (infants aged <7 days) Study‐2: 1. Aged <2 months 2. Admitted to the study hospitals with relatively higher‐mortality risk signs of CSI at presentation (not feeding well, movement only on stimulation, low body temperature <35.5°C, two or more of the six signs of CSI) 3. Clinically well on day 3 defined as absence of all signs of critical illness (not feeding at all, no movement at all, convulsions) or CSI (not feeding well, movement only when stimu